<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>父子双向通信</title>
</head>
<body>
  <div id="app">
      <cpn :number1="num1" 
           :number2="num2"
           @num1change="num1change"
           @num2change="num2change"
      ></cpn>
  </div>

  <template id="cpn">
    <div>
      <h2>props: {{number1}}</h2>
      <h2>data: {{dnumber1}}</h2>
      <!-- <input type="text" v-model="dnumber1"> -->
      <input type="text" :value="dnumber1" @input="num1Input">
      
      <h2>props: {{number2}}</h2>
      <h2>data: {{dnumber2}}</h2>
      <!-- <input type="text" v-model="dnumber2"> -->
      <input type="text" :value="dnumber2" @input="num2Input">

    </div>
  </template>

  <script src="../js/vue.js"></script>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        num1: 1,
        num2: 0
      },
      methods: {
        num1change(value) {  //value是字符串类型
          console.log(typeof value)
          this.num1 = parseFloat(value)
        },
        num2change(value) {
          console.log(typeof value)
          this.num2 = parseFloat(value)
        }
      },
      components: {
        cpn: {   
          template: '#cpn',
          props: {     //使用props把data值传给子组件
            number1: Number,
            number2: Number
          },
          data() {
            return {
              dnumber1: this.number1,
              dnumber2: this.number2
            }
          },
          methods: {
            num1Input(event) {
              //1.将input中的value赋值到dnumber中
              this.dnumber1 = event.target.value;

              //2.为了修改父组件，发出一个事件
              this.$emit('num1change',this.dnumber1)

              //3.同时修改dnumber2的值
              this.dnumber2 = this.dnumber1 * 100
              this.$emit('num2change',this.dnumber2)
            },
            num2Input(event) {
              this.dnumber2 = event.target.value;
              this.$emit('num2change',this.dnumber2)

              this.dnumber1 = this.dnumber2 / 100
              this.$emit('num1change',this.number1)
            }
          },
        },
        
      }
    })
  </script>
</body>
</html>